새로운 할인 정책으로 변경, 개발

package hello.core.discount;
  import hello.core.member.Grade;
  import hello.core.member.Member;
public class RateDiscountPolicy implements DiscountPolicy { private int discountPercent = 10; //10% 할인
      @Override
      public int discount(Member member, int price) {
 if (member.getGrade() == Grade.VIP) {
               return price * discountPercent /  100;
          } else {
return 0; }
} }

테스트 코드 작성

package hello.core.discount;

import hello.core.member.Grade;
import hello.core.member.Member;
import org.assertj.core.api.Assertions;
import org.junit.jupiter.api.DisplayName;
import org.junit.jupiter.api.Test;

import static org.assertj.core.api.Assertions.*;
import static org.junit.jupiter.api.Assertions.*;

class RateDiscountPolicyTest {
    RateDiscountPolicy discountPolicy = new RateDiscountPolicy();

    @Test
    @DisplayName("VIP는 10% 할인이 적용되어야 한다")
    void vip_o(){
        //given
        Member member = new Member(1L,"memberVIP", Grade.VIP);
        //when
        int discount = discountPolicy.discount(member,10000);
        //then
        assertThat(discount).isEqualTo(1000);
    }
    @Test
    @DisplayName("VIP가 아니면 10% 할인이 적용되지 않아야 한다")
    void vip_x(){
        //given
        Member member = new Member(2L,"memberBASIC", Grade.BASIC);
        //when
        int discount = discountPolicy.discount(member,10000);
        //then
        //Assertions.assertThat(discount).isEqualTo(1000);//할인금액은 0이 되야함.
        assertThat(discount).isEqualTo(0);//할인금액은 0이 되야함.
    }
}